Battuto literally means 'beaten, whipped', like a beaten egg (uovo battuto). But most commonly it is used as another word for soffritto or a French mirepoix: a mix of finely chopped stuff that is the base for a soup or sauce. Usually it's onion, garlic and celery or parsley, fried in olive oil. Sometimes it may include prosciutto, pancetta or lardo, maybe carrot and celery, olives, capers or other ingredients.
A battuto alla romana is parsley, celery, lardo and onion (and sometimes garlic). With the addition of tomato, a big battuto can become a very simple soup: minestra al battuto.
Battuto di chianina (or some other kind of meat) is raw meat 'whipped with a knife' into tiny bits, or steak tartare
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